Floor standing mainframe computer



FIG. 1 is a top front and left side perspective view of a floorstanding mainframe computer showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a top plan view thereof; and,

FIG. 4 is a left side elevational view thereof, the right side elevational view being identical in appearance. 

The ornamental design for a floor standing mainframe computer, as shown and described. 